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From:   Arun KS <arunks.linux@gmail.com>
Date:   Sun, 8 Nov 2020 20:41:36 +0530
Message-ID: <CAKZGPAPGP7=_W8c5DA5E0eKmawF10XSO92_+E4hSE1cNFE_vcA@mail.gmail.com>
Subject: Re: [PATCH] pinctrl: msm: Use dynamic GPIO numbering
To:     Linus Walleij <linus.walleij@linaro.org>
Cc:     Bjorn Andersson <bjorn.andersson@linaro.org>,
        MSM <linux-arm-msm@vger.kernel.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Timur Tabi <timur@codeaurora.org>,
        Arun KS <getarunks@gmail.com>
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On Thu, Nov 5, 2020 at 3:46 PM Linus Walleij <linus.walleij@linaro.org> wrote:
>
> On Fri, Oct 23, 2020 at 4:21 PM Arun KS <arunks.linux@gmail.com> wrote:
>
> > Im only concerned because, after this change, the use of gpio number
> > from user space has become a little difficult.
>
> This makes me a bit puzzled so I need to push back a bit
> here.
>
> What is this userspace and what interface is it using?
>
> We recommend using the GPIO character device with
> libgpiod for userspace applications:
> https://www.kernel.org/doc/html/latest/driver-api/gpio/using-gpio.html

Thanks Linus. Makes sense. Basically using the gpiochipset and offset
to it will solve my problem. Earlier, while using the sysfs interface,
it used to be one to one mapping with real gpio numbers.

Regards,
Arun
>
> Is there any problem with this?
>
> sysfs is deprecated for years now:
> https://www.kernel.org/doc/html/latest/admin-guide/gpio/sysfs.html
>
> Yours,
> Linus Walleij